DTC 49: Cal FR Brake Fluid Pressure Sensor Center Position Error

Turn the ignition switch ON (II).
Clear the DTCs with the HDS.
Watch the adaptive cruise control (ACC) indicator.
Does the ACC indicator stay off?

YES - Go to step 4.

NO - Go to step 5.
Press the brake pedal, and watch the ACC indicator.
Does the ACC unit indicator stay off?

YES - The system is OK at this time. Check for loose or poor connections.

NO - Go to step 5.
Check for DTCs with the HDS.
Is DTC 49 indicated?

YES - Go to step 6.

NO - Troubleshoot the indicated DTC(s). If there are no DTCs, the system is OK at this time.
Turn the ignition switch OFF.
Disconnect the 20P connector from the ACC unit.
Check for continuity between the ACC unit 20P connector No. 5 terminal and body ground.

Fig 1: Checking For Continuity Between ACC Unit 20P Connector No. 5 Terminal And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES - Repair a short to ground in the wire between the ACC unit and the right front pressure sensor.

NO - Go to step 9.
Disconnect the 3P connector from the right front pressure sensor.
Connect the right front pressure sensor 3P connector No. 2 terminal to body ground with a jumper wire.

Fig 2: Connecting Right Front Pressure Sensor 3P Connector No. 2 Terminal To Body Ground With Jumper Wire
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Check for continuity between ACC unit 20P connector No. 5 terminal and body ground.

Fig 3: Checking For Continuity Between ACC Unit 20P Connector No. 5 Terminal And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there about 5V?

YES - Go to step 12.

NO - Repair a short to ground in the wire between the ACC unit and the right front pressure sensor.
Remove the jumper wire from the right front pressure sensor.
Reconnect all connectors.
Turn the ignition switch ON (II).
Measure the voltage between the ACC unit 20P connector No. 3 and No. 5 terminals.

Fig 4: Measuring Voltage Between ACC Unit 20P Connector No. 3 And No. 5 Terminals
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there about 5V?

YES - Go to step 16.

NO - Check for loose or poor connections. If OK, replace the ACC unit (see DISTANCE SWITCH TEST ).
Turn the ignition switch OFF.
Disconnect the 20P connector from the ACC unit
Check for continuity between the ACC unit 20P connector No. 6 terminal and body ground.

Fig 5: Checking For Continuity Between ACC Unit 20P Connector No. 6 Terminal And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES - Repair a short to ground in the wire between the ACC unit and the right front pressure sensor.

NO - Go to step 19.
Disconnect the 3P connector from the right front pressure sensor.
Connect the right front pressure sensor 3P connector No. 3 terminal to body ground with a jumper wire.

Fig 6: Connecting Right Front Pressure Sensor 3P Connector No. 3 Terminal To Body Ground With Jumper Wire
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Check for continuity between the ACC unit 20P connector No. 6 terminal and body ground.

Fig 7: Checking For Continuity Between ACC Unit 20P Connector No. 6 Terminal And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES - Go to step 22.

NO - Repair an open in the wire between the ACC unit and the right front pressure sensor.
Check for continuity between the ACC unit 20P connector No. 5 terminal and body ground.

Fig 8: Checking For Continuity Between ACC Unit 20P Connector No. 5 Terminal And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES - Repair a short in the wire between the PRESS FR line and VCC line.

NO - Go to step 23.
Check for continuity between the ACC unit 20P connector No. 3 terminal and body ground.

Fig 9: Checking For Continuity Between ACC Unit 20P Connector No. 3 Terminal And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES - Go to step 24.

NO - Repair an open in the wire between the ACC unit and the right front pressure sensor.
Remove the jumper wire from the right front pressure sensor.
Reconnect all connectors.
Turn the ignition switch ON (II).
Check the brake switch signal (BRAKE SW (N. O.)) with the HDS.
Does the indication show ON when the brake pedal is pressed, and show OFF when the brake pedal is released?

YES - Go to step 29.

NO - Go to step 28.
Check for DTCs with the HDS.
Is DTC 49 indicated?

YES - Go to step 30.

NO - Go to step 29.
Check for DTCs with the HDS.
Is DTC 60, 110, or 111 indicated?

YES - Troubleshoot the indicated DTC.

NO - Troubleshoot the brake pedal position switch circuit (see HIGH MOUNT BRAKE LIGHT REPLACEMENT ).
Measure the voltage between the ACC unit 20P connector No. 3 and No. 6 terminals.

Fig 10: Measuring Voltage Between ACC Unit 20P Connector No. 3 And No. 6 Terminals
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there about 0.5V?

YES - Go to step 31.

NO - Replace the right front pressure sensor (see BRAKE FLUID PRESSURE SENSOR REPLACEMENT ).
Clear the DTCs with the HDS.
Watch the ACC unit indicator.
Does the ACC unit indicator stay off?

YES - The system is OK at this time. Check for loose or poor connections.

NO - Go to step 33.
Check for DTCs with the HDS.
Is DTC 49 indicated?

YES - Check for loose or poor connections. If OK, replace the ACC unit (see DISTANCE SWITCH TEST ).

NO - Troubleshoot the indicated DTC(s). If there are no DTCs, the system is OK at this time.